Cullen Jenkins knows he’s coming to a Giants team that has won two Super Bowls since 2007 and that, despite his impressive NFL resume, he is going to have to prove himself to his new team.

“It has to be something you earn,’’ Jenkins said yesterday on giants.com after signing his three-year, $8 million contract. “It’s going to take a lot of work, especially on my part, to come in and make sure I’m fitting in with the team. I have to be willing to do whatever they ask of me and help out the best I can.”

Jenkins, 32, figures to fit right in as a starting defensive tackle, replacing Chris Canty, who was released. Jenkins was a starter for the Packers on their 2010 Super Bowl championship team and spent the past two years with the Eagles before they cut him Feb. 25.

General manager Jerry Reese said Jenkins “brings the physical nature that we like and also gives us a lot of flexibility up front.” Coach Tom Coughlin said Giants players have high regard for Jenkins based on what he’s done against them as an opponent.

Jenkins has played against the Giants seven times, including four times in the past two years.

Co-owner John Mara said Jenkins “was one of the highest players we had graded of all the free agents’’ and added the pro personnel and coaching staff “all loved him.”

“As I understand it, even [guard] Chris Snee was very much in favor of signing him because he’s been such a tough opponent for him over the years,” Mara said. “He’ll give us a certain toughness on that defensive line.”

* Running back Andre Brown and safety Stevie Brown as restricted free agents both received second-round tenders, which will pay them $2.02 million for the 2013 season. The Giants are also interested in re-signing running back Ryan Torain.

* Mara said “hopefully’’ when asked if right tackle David Diehl will be back, which sounds as if Diehl might be asked to take a pay cut.

* Why not extend Eli Manning’s contract in order to cut back some of the NFL-high $20.85 million he’ll count against the 2013 salary cap?

“That’s always an option at some point in time,’’ Mara said. “But he’s proven to be worth the salary cap space that’s been allocated to him. That’s not on our radar right now.”